U.S. Pat. No. 4,616,640 for a "Birth Control Method and Device Employing Electric Forces"--issued Oct. 14, 1986--by Steven Kaali, Peter M. Schwolsky and Joseph W. Porter-inventors, discloses a novel method and device using electric forces within and about the cervical canal of a female for acting on male sperm and preventing migration of the male sperm through the cervical canal and into the uterine cavity where it might fertilize an egg.